Akbar, M., E. Wijaya, and K. Astuty. “The Influence of Digital Marketing, Social Media, Promotion and Influencers on Purchasing Decisions for Iphone Products”. International Journal on Economics, Finance and Sustainable Development, Vol. 6, no. 12, Dec. 2024, pp. 324-35, https://journals.researchparks.org/index.php/IJEFSD/article/view/5340.